Grass mowing machines such as ZTR mowers may have internal combustion engines mounted at the rear of the mower frame or platform behind the operator seat. ZTR mowers also have at least one independently powered drive wheel on each side of a frame. Hydrostatic transmissions transmit power from the engine to each of the left and right drive wheels, either in forward or reverse. The pair of hydrostatic transmissions, or dual hydrostatic transmission, may be driven through a belt and pulley arrangement by the engine crankshaft. The hydrostatic transmission(s) may be mounted to the rear of the vehicle frame adjacent the engine, under and/or behind the operator seat. For example, the hydrostatic transmission(s) may be bolted to mounting plates that are welded to the frame or engine mounting platform. Other rear mounted components, such as a roll over protection system (“ROPS”), also may be welded or attached with bolts to brackets fastened to the frame behind the operator seat.
The mounting plates and structures used for mounting the engine and other components to the rear of the mower frame are labor intensive to weld, fabricate and inspect due to the high number of parts that go into the assembly. They require a large number of welds to securely connect together the engine platform, supporting panels, and brackets. It would be desirable to simplify the mounting structures for the engine and hydrostatic transmission(s) on the rear of a ZTR mower. It would be desirable to provide a low cost mounting structure for the engine and hydrostatic transmission on a ZTR mower. It would be desirable to reduce the amount of labor to mount an engine, hydrostatic transmission and other components on the rear of a ZTR mower.